Phase coherent, low cost, 4th order XO - diyAudio
Go Back   Home > Forums > Amplifiers > Solid State

Solid State Talk all about solid state amplification.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 13th April 2003, 02:09 PM   #1
diyAudio Member
 
Join Date: Dec 2002
Location: dry ol Melbourne Australia
Question Phase coherent, low cost, 4th order XO

Off the top of the head:

1. Rod Elliot’s ESP project
http://sound.westhost.com/project09.htm
Even with revision, modelling with circuit design shows that this is not phase coherent

2. Behringer 3-way CX (3400 ). http://www.behringer.com/02_products...X3400&lang=eng
Costs about the same as a Elliot ESP (including components about $US 150), ready made and adjustable.
But is it phase coherent?

3. DYO (Design your own) requires reasonable skill/ knowledge.

4. Other?


Non phase coherent XOs could be fixed, with phase correction.


Scenario A: Active

Scenario B: Passive
Best option

Richard
  Reply With Quote
Old 13th April 2003, 02:59 PM   #2
Banned
 
Join Date: Dec 2001
Location: Zamboanga, City of Flowers, Mindanao
Send a message via Yahoo to Elso Kwak
Lightbulb Bessel?

Hi Rick57,
How about Bessel characteristic?
What do you mean by phase coherent? I am not familiar with the term.
  Reply With Quote
Old 13th April 2003, 04:32 PM   #3
Hartono is offline Hartono  Indonesia
diyAudio Member
 
Join Date: Nov 2002
Location: currently in China
Default 1st order phase characteristic

Elso, maybe rick57 meant : phase coherent= minimum phase

  Reply With Quote
Old 13th April 2003, 04:52 PM   #4
Banned
 
Join Date: Dec 2001
Location: Zamboanga, City of Flowers, Mindanao
Send a message via Yahoo to Elso Kwak
Question Minimum Phase

Quote:
Originally posted by Hartono
Elso, maybe rick57 meant : phase coherent= minimum phase

Hi Hartono,
I am sorry what do you mean by Minimum Phase?. I am not familiar with the term....
  Reply With Quote
Old 13th April 2003, 05:05 PM   #5
Hartono is offline Hartono  Indonesia
diyAudio Member
 
Join Date: Nov 2002
Location: currently in China
minimum phase , linear phase , phase coherent crossover
means that the crossover does not produce phase distortion

thus in systeum using XO with linear phase characteristic will produce summed output waveform with flat magnitude and phase characteristic.


traditionally this means using 1st order butterworth network, however some people have used various method to compensate for phase error in some active XO design so that the XO can be of higher order (steeper roll off) and still have the characteristic of 1st order butterworth network



I hope this might help
  Reply With Quote
Old 13th April 2003, 09:15 PM   #6
Pedja is offline Pedja  Serbia
diyAudio Member
 
Join Date: Jun 2002
Location: Belgrade
Some other terms are in use also. There were good articles about it by John Kreskovsky, but unfortunately I just discovered he removed (it seems it happened yesterday!) whole content of his site. Phase coherent system is that which at its output shows the same relations between the phases as it was at the input. If phase coherent system has flat amplitude response then it can be considered as transient accurate, i.e. it will have good transient behavior. In itself, it is not an exclusive privilege of the first order crossovers.

Richard, you should ask this question rather in the loudspeaker forum. But, when you asked already…

I’d rather never use 24dB crossover. Be it active or passive, phase coherent or not.

When you correct phase of the non phase coherent crossover, you get the phase coherent crossover, we are walking in circle with it.

There is a bulk of the crossover simulators, so you can model crossover day and night. Linkwitz-Riley is not the only way to achieve phase coherent crossover.

Pedja
  Reply With Quote
Old 14th April 2003, 02:37 AM   #7
Hartono is offline Hartono  Indonesia
diyAudio Member
 
Join Date: Nov 2002
Location: currently in China
Wink 2nd & 4th order linkwitz rilley is not phase coherent

nt
  Reply With Quote
Old 14th April 2003, 03:42 AM   #8
diyAudio Member
 
Join Date: Dec 2002
Location: dry ol Melbourne Australia
Question Is the test for "not phase coherent" valid

See:

Which 4th order XOs are phase coherent? Are SWs of value?
  Reply With Quote
Old 14th April 2003, 04:57 AM   #9
Hartono is offline Hartono  Indonesia
diyAudio Member
 
Join Date: Nov 2002
Location: currently in China
Wink it the summed output doesn't resemble square wave then it's not phase coherent

nt
  Reply With Quote
Old 14th April 2003, 05:00 AM   #10
diyAudio Member
 
Join Date: Dec 2002
Location: dry ol Melbourne Australia
Question Are u sure that the square wave is valid for music? (nt)

Maybe its not that relevent for music
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Are single drivers really phase coherent? chuck55 Full Range 46 30th March 2010 06:03 AM
About a Nelson Pass phase coherent crossover gaetan8888 Pass Labs 4 1st October 2007 10:44 PM
Which 4th order XOs are phase coherent? Are SWs of value? rick57 Multi-Way 0 14th April 2003 03:40 AM
Linkwitz-Riley 24dB/octave Phase Coherent Crossover djdan Solid State 30 25th September 2002 10:32 PM


New To Site? Need Help?

All times are GMT. The time now is 06:58 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright ©1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2